Organic Disorders of Language Dr Alex Davies ST4 General Adult Psychiatry

Aims and Objectives Highlight the organic disorders of language – Language and the brain – Receptive (Sensory) dysphasia – Motor (Expressive) dysphasia – Aphasia – Dysarthria – Aphonia

Wernicke’s Area Lies in the left temporal lobe, posterior section of the superior temporal gyrus Processes auditory words and language inputs: Represent words Interpret understand written words and language Produce speech ArteryMiddle cerebral VeinSuperior sagittal sinus

Broca’s Area Lies in the left frontal lobe, inferior frontal gyrus Responsible for language production: Process sounds making up words (phonemes) Produce verbal output Activate the motor centres of the tongue and mouth Remember verbal material ArteryMiddle cerebral VeinSuperior sagittal sinus

Inferior Parietal Lobule Located at the junction of temporal, occipital, and parietal lobes Processes many stimuli (auditory, visual, sensorimotor, etc.) simultaneously Adds on multiple properties of spoken and written words, eg)sound, appearance, and functioning Classifies and label things Form concepts and think abstractly Two distinct parts: 1. Supramarginal gyrus 2. Angular Gyrus

Language Components of language: Fluency –intact Broca’s area and it’s connections Comprehension – intact Wernicke’s area and it’s connections with association cortex and sensory input Repetition – requires no high level processing

Language Tasks Signals from Broca’s area relied to motor area to coordinate the delivery of language via tongue, lips and vocal cords Fasciculus connects Wernicke’s to Brocca’s Broca’s area is the higher motor area of language production Wernicke’s area and auditory association cortex Processes language component Sound transmitted through ears to primary auditory cortex

Language Tasks Broca’s area – words arranged Wernicke’s area Recognised and associated to auditory form Angular gyrus Read a word – primary visual cortex

Dysphasia Dysphasia – impairment in comprehension or production of language whether spoken or written – Receptive (Sensory) – Expressive (Motor) Aphasia is a complete loss of language comprehension or production (often dysphasia and aphasia are used interchangeably, which can be confusing!)

Dysphasia

Receptive Dysphasia Receptive (sensory or fluent or ”jargon”) dysphasia is due to a lesion in Wernicke's area Results in the inability to understand language correctly, both spoken and written Speech is fluent but disorganised, voluminous but uninformative Often a combination of expressive and receptive dysphasia, as the two areas are closely related anatomically

Expressive Dysphasia Expressive (motor) dysphasia is due to a lesion in Broca's area of the brain Results in difficulty in speech output Speech is severely reduced and is limited to short utterances, few words. Vocabulary access is limited and the formation of sounds is laborious and clumsy

Fluent/Non-fluent Dysphasia In reality, it is not always that clear cut. People do not always fall neatly into one type of dysphasia FluentNon-fluent Normal speed and intonation Slow and hesitant Nonsense words/jargonArticulation errors Poor self-monitoring and awareness of errors Understanding is usually intact Often poor understanding

Dysphasia Fluent “Well this is…mother is away here working her work out here to get her better, but when she’s looking, the two boys looking in the other part” Non-fluent “Cookie jar…fall over…chair…water…empty”

Types of Dysphasia TypesFluencyRepetitionComprehensionNaming Wernicke’s sensory  Broca’s motor  Conduction dysphasia   Transcortical sensory  Transcortical motor 

Alexia Alexia/Pure word blindness (alexia without agraphia) Can speak normally and understand spoken language Can write but cannot read Results from damage to left occipito-temporal region Centre for optic images of letters in left angular gyrus is isolated from both visual cortices The language centre cannot be accessed by visual stimulation therefore the patient cannot read

Dysphasia’s Pure word deafness (auditory verbal agnosia) Comprehension impaired of spoken language only Hearing, speech, reading and writing remain intact Pure agraphia Inability to write and spell (other faculties of language preserved)

Dysarthria Dysarthria – disorder of articulation Motor speech disturbance resulting from neurological damage May be due to lesions in brain stem (bulbar), cortex (pseudobulbar), cerebellum or extrapyramidal system Varies from mild slurring to complete unintelligible speech, in which case it is difficult to distinguish from aphasia Comprehension, reading and writing should not be affected, in contrast to aphasia Numerous types – spastic (bilateral UMN), flaccid (bilateral or unilateral LMN), ataxic (cerebellum), hyper/hypokinetic (basal ganglia) mixed, drug induced

Aphonia Aphonia – inability to vocalise Refers to sound production rather than manipulation (dysarthria) Whispering may occur May occur secondary to structural disease affecting the vocal cords, the 9 th cranial nerve (glossopharyngeal) or higher centres. Or functional illness where underlying vocal cord function is normal

Disorders of Volition

Volition Volition “Will” – a goal-directed striving or intention based on cognitively planned motivation “Will has a consciously conceived goal accompanied with awareness of the necessary means and consequences. It implies decision making ability, intention and responsibility” (Jaspers 1959) Abnormalities of will: – Absence or loss, resulting in apathy in schizophrenia and depression – Oscillating will, resulting in indecisiveness, ambivalence or ambitendency – Anomalous will in passivity experiences and made actions

Volition in Schizophrenia In schizophrenia the disturbance of volition is mostly seen in the negative traits - emotional apathy - ambivalence - poverty of speech - lack of drive - social withdrawal Patient believes their food is being poisoned refrains from eating – a deliberate act of will Patient withdraws from normal social interaction, lack of motivation to continue employment – loss of volition

Volition in Schizophrenia Passivity of volition – delusional control (first rank symptoms): – Made feelings: emotions experienced as not being patient’s own – Made impulses: external imposition of an impulse to act, but if performed, the act is experienced as the patient's own – Made acts: the body executes acts under external control

Volition in Affective Disorders Disturbances of volition in affective disorders are associated with abnormalities of activity, retardation in depression and over activity in mania Depression – motivation is impaired rather than will, alongside loss of ability to experience enjoyment (anhedonia) Mania - commonly presents with increased activity and initiate all sorts of new projects, but many are not carried out to completion

Volition in Organic Disorders Biological drives such as appetite, sleep and thirst are located anatomically in and around the midbrain Structural disease or biochemical changes (hormonal, metabolic) can disturb volition Physical illness can have specific and generalised effects on volition Eg) Excessive thirst and polydypsia occur with disease of posterior pituitary or nephrogenic diabetes insipidus (lithium treatment)

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